Bantu jawab ya. Tolong

8) Vp/Vs = Np/Ns
240/12 = Np/Ns
20/1 = Np/Np
20:1 = Np:Ns

9) diket: Pp = 800 watt
Vp x Ip = Pp
Vp x Ip = 800 watt
t = 15 menit = 900 sekon
Vp x Ip x t = Wp
800 watt x 900 sekon = 720.000 Joule
Wp = Ws (karena trafo dianggap ideal)
karena ada pengurangan energi sebesar 108.000 Joule di dalam trafo maka:
Ws = Wp - 108.000 joule
Ws = 720.000 - 108.000
Ws = 612.000 joule
efisiensi trafo = Ws/Wp x 100%
n = 612.000/720.000 x 100%
n = 85%

10) diket: Np = 500, Ns = 5000 dan Vp = 220V
Np/Ns = Vp/Vs
500/5000 = 220/Vs
1/10 = 220/Vs
Vs = 10x220 : 1 = 2200 Volt
jadi nilai tegangan keluaran = Vs = 2200 volt